Light-buoy and method for feeding same



I Aug. 31, 1937.

F. JAEDICKE LIGHT BUOY AND METHOD FOR FEEDING SAME Fi-led' March so, 1933 2 sheets-sheet 1 i A t I "i -5 4. j j

Inventor: FQ/G ZIa/(Q Aug. 31, 1937.

/n ventom j -dlaki -2 Sheets-Sheet 2 Patented Aug. 31, 1937 UNITED STATES PATENT OFFICE Friedrich Jaedicke, Berlin-Schmargendorf, Germany, assignor to N. V. Machinerieen-en Apparaten Fabrieken Meaf, Utrecht, Netherlands Application 2 Claims.

The present invention relatesto light-buoys floating in water and provided with a supply of gaseous fuel and the invention has for its object to produce and use such light-buoys which require less material, cause less loss of gaseous fuel and can be refilled with gas in a simple manner while they are on the water.

It has already been proposed to fill light-buoys with liquid fuels such as petroleum and to produce a gas pressure over these liquid fuels within the buoy, the said pressure forcing the liquid through a tube to the lamp secured over the buoy. However, the use of liquid fuels has great drawbacks which reside inter alia in the thickening which these liquids undergo at low temperatures and which reside in the necessity of gasifying these liquid fuels in special apparatus for obtaining an economical combustion.

For this reason the attempt has been made to use gaseous fuels by compressing them in special steel flasks or cylinders and inserting the latter in the light-buoys. This construction has also great drawbacks because if it were desired to fill gas into the light-buoys for a sufficiently long burning period, a large number of steel flasks or cylinders would be required for that purpose. The replacing of these steel flasks or cylinders in connection with the floating buoys from the boat was very difficult owing to their great weight. Moreover, very large buoys of sufficient carrying capacity were required. Finally, in order to avoid :these steel flasks or cylinders, it was proposed to produce the gas within the lightbuoy itself by mixing calcium carbide with water in the knownv manner. Even in this case it was difficult to insert the materials in the buoys floating on the water and subjected to the waves. Moreover, it was necessary toremove the residues from the buoys before they were refilled.

Finally, an attempt was made to fill highly compressed gas directly into the light-buoys themselves. However, for that purpose, lightbuoys having a great wall thickness were required in order to enable them to resist the necessary high working pressures of 150 atmospheres and more. Consequently, the buoys were very heavy and did not sufficiently emerge from the water. However, in order to obtain a greater buoyancy, it was necessary to again increase the wall thickness.

All these difficulties can be avoided by using light-buoys having a combustible gas which is gaseous at ordinary temperature and atmospheric pressure, that is to say which does not require any special means for its gasification but which March 30, 1933, Serial No. 663,589 In Germany April 1, 1932 on the other hand is liquefiable at a low pressure and at a temperature which is only slightly below the outer temperature. This lower temperature is obtained, according to the present invention, by storing the combustible gases in a to the buoy may be effected in a simple manner by mean-s of small pumps. After consumption of the gas, it is not necessary to removeany residues from the buoy but it is suflicient to fill the same again. With regard to the gases which have the said properties, propane and butane gas are specially adapted for such floating lightbuoys, although any gas may be used which is liquid at a temperature of 15 C. and a pressure within the range of atmospheric pressure to 8 atmospheres thereabove. Propane gas for example is gaseous at atmospheric pressure and ordinary outer temperature. It has a very high calorific value of 21000 kgcal./cm. In the case of an ordinary temperature of +15 C., liquefaction is possible even with the low pressure of 6.2 atmospheres. It is possible at this pressure to provide 127000 kg-cal. in a. receptacle having a capacity of 27 liters while the safety pressureof the receptacle need only amount to 25 atmospheres. Similar conditions also apply to butane. If a receptacle having the same capacity as that disclosed above were to receive oil gas of 100 atmospheres, it must be able to withstand a safety pressure of 190 atmospheres. The weight of the receptacle would thereby be increased 50%, while only 30000 kg-cal. can be accommodated therein.

The very large quantity of heat units which can be accommodated in a small receptacle when using propane or butane gas, has the further advantage that instead of utilizing the entire hollow space of the light-buoy for filling the same with combustible gas and making the entire light-buoy sufliciently gas-tight, it is possible to provide within the light-buoy only a small gas-tight and pressure resistant receptacle, the major portion of which is located at a place below the water level and in constant heat transfer relationship with the water. The remaining part of the light-buoy need only be as strong as is necessary for the buoyancy.

With reference to the accompanying drawings: Figure 1 shows in elevation and partial section a buoy according to the present invention.

Fig. 2 is a horizontal section along line AB of Fig. 1.

Fig. 3 is a similar view of Fig. 1 with a special tank.

Fig. 4 is a modification of Fig. 3; and Fig. 5 still another modification of the buoy. Reference numeral I indicates the body of the buoy which carries the signal lamp 3 on a frame 2. If the buoy is adapted for deep water, it is provided With a tail pipe or weight 4 for giving the buoy a certain stability. The gas is admitted through the pressure valve 5 directly into the body I of the buoy, so that it is mostly col- I lected in the part of the buoy below the water level. The result is thus obtained that the gas is always maintained at the temperature of the water and an inadmissible superpressure in the body of the buoy cannot be developed. In the lower part of the buoy, in which the liquid gas is stored, preferably bulkhead-like walls 6 are inserted which are provided with small holes 9, whereby the movement of the liquid is considerably checked or retarded. Lurch tanks or the like may also be built in, which are adapted to prevent an excessive movement of the liquid in a rough sea. The gas is taken from the buoy body through the pipe I and supplied to the signal lamp 3. Figure 2 is a section of Figure 1 on line A-B and shows the arrangement of the bulkheads 6.

Figure 3 is another constructional form of a buoy according to the present invention. The outer structure is the same as in Figure 1. However, the gas is not admitted directly into the buoy body I but into a separate tank 8 which is arranged along the vertical axis of the buoy. According to this constructional form, the liquid gas is also kept mainly below the outer water level.

Figure 4 shows how the stationary tank 8 for the gas can be provided in the tail pipe 4 of the buoy. A pipe I is used for connecting tank 8 through pressure valve with the signal lamp 3 and for filling tank 8 through valve 5. The other parts of the buoy are constructured as already described in connection with Figures 1 to 3. This construction has been found to be of great advantage since the gas tank is always completely surrounded by water and therefore effectively cooled, and because the weight of the tank and the gas is used for steadying the buoy and for maintaining it in upright position, While Fig. 5 shows a construction similar to that shown in Fig. 4 in which several tanks 8 of removable character can be stored. These tanks 8 have comparatively thin walls since they have to withstand only relatively low pressure because of the cooling action of the surrounding water.

The pressure in atmospheres of propane and butane at varying temperatures as shown by the chart in the Oil and Gas Journal for February 25, 1932, pages 52 and 53, are substantially as follows:

Temperature Propane Butane I claim:

1. The method of maintaining in operative condition a light buoy adapted to float in water and use a fuel fluid which is a liquid at a temperature of 15 centigrade and a pressure substantially within the range of from atmospheric pressure to eight atmospheres thereabove and gaseous at normal temperature and pressure, which comprises filling said buoy with said fluid at a pressure and temperature within said range of liquefaction, storing said fluid within said buoy with the buoy partially submerged in water while in I use and said fluid in heat transfer relation with the water thereby maintaining said fluid within said pressure and. temperature range of liquefaction.

2. The method of maintaining in operative condition a light buoy adapted to float in water and use a fuel fluid which is a liquid at a temperature of 15 centigrade and a pressure substantially within the range of from atmospheric pressure to eight atmospheres thereabove and gaseous at normal temperature and pressure, which comprises introducing said fluid into said buoy with said fluid at a pressure and temperature within said range of liquefaction, storing said fluid within said buoy with the buoy partially submerged in water while in use and maintaining said fluid in said buoy within said pressure and temperature range of liquefaction. 

